Multitasking: The Brain Seeks Novelty

This is my first blog post for the Huffington Post, so let me start by introducing myself. I'm a neuroscientist at the University of Texas at Austin, where I use brain imaging to study how the human mind achieves its amazing feats and why it sometimes fails. In this blog I plan to focus on how neuroscience and psychology can provide us with clues about how to live better, focusing on topics related to multitasking and information overload.

I will start by admitting up front that I am an information junkie. Try as I might, it's difficult for me to make it through an hour-long meeting without peeking at my iPhone at least once to check my email, and I have, on more than one occasion, come close to hurling myself down the stairs as I try to read emails while descending. Why would I do things that place me in such clear social and physical peril? Part of the answer lies in the brain's response to novelty.

The brain is built to ignore the old and focus on the new. Marketers clearly understand this: If you watch closely, you will notice that heavily-played television ads will change ever so slightly after being on the air for a few weeks. When this change is detected by the brain, our attention is drawn to the ad, oftentimes without us even realizing it. Novelty is probably one of the most powerful signals to determine what we pay attention to in the world. This makes a lot of sense from an evolutionary standpoint, since we don't want to spend all of our time and energy noticing the many things around us that don't change from day to day.

Researchers have found that novelty causes a number of brain systems to become activated, and foremost among these is the dopamine system. This system, which lives deep in the brain stem, sends the neurotransmitter dopamine to locations across the brain. Many people incorrectly think of dopamine as the "feel-good" neurotransmitter because drugs that create euphoria, such as cocaine and methamphetamine, cause an increase of dopamine in particular parts of the brain. However, a growing body of research shows that dopamine is more like the "gimme more" neurotransmitter.

Some of the most interesting research on this topic has been done by Kent Berridge and his colleagues at the University of Michigan. In this research, they videotape rats and then measure how often the rats exhibit signs of pleasure; some wonderful video of these "affective reactions" can be found at Berridge"s web site. Their research has shown that blocking dopamine in the brain doesn't affect how often the rats exhibit these pleasure responses. Instead, it reduces the rats' motivation, turning them into rodent slackers. Another neurotransmitter system in the brain, the opioid system, seems to be the one that actually produces the pleasurable sensations, though it too has very close relations with the dopamine system.

Another interesting fact about dopamine is that nearly every drug that people abuse has an effect on the dopamine system (as do chocolate, money, sex, and many other addictive things). Again, the role of dopamine is not in the pleasure that one may get from the drug, but in establishing the craving that keeps one coming back for more, even after the drug has lost its pleasurable effects.
A final important fact about dopamine is that it is very much involved in learning and memory. Learning and memory occur in the brain through changes in the way that neurons connect to one another. We know that the brain is very "plastic," meaning that it can change drastically with experience. However, the brain needs some way to control these changes; after all, we wouldn't want our entire visual system to be rewired to see upside down after doing a single handstand. Dopamine is one of the neurotransmitters that controls this: When dopamine is released, it is a signal to the brain that is it now time to start learning what is going on.

So what does this all have to do with my iPhone? Well, it's hard to imagine a more powerful novelty-generating device than this little 4.8-ounce hunk of metal and glass. Every time it buzzes to signal a new email or text message, it is wiring even more firmly into my brain the desire to pick up the device and look for that precious nugget of new information (which usually turns out to be something completely mundane, like a reminder of another committee meeting). Although there is not yet any published research on this, I am confident that we will soon see that our bond to these devices works through the same mechanisms in the brain that govern addiction to drugs, food, and many other things.

Given all of this, what can we do to prevent ourselves from becoming novelty-seeking zombies? The first thing is to simply become mindful of one's use of media and devices. I find that one of the best things to do is to institute regular vacations from email. It usually takes a couple of days for the itch to check my email every five minutes to go away, and watching it happen reminds me just how obsessed I can become, but it also shows that it's possible to lead a perfectly normal and fulfilling life without constant email access. Once we see that we can live without constant access to our devices, we can start trying to exert some control over device use in our daily lives. Evolution gave us the ability to overcome our urges, but we have to have the will to employ this control. One bit of good news is that we can improve our self-control with practice; more on that in a future post.